Experimental Study on Tool Parameters of Al2O3 in High Speed Machining

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1 International Journal of Current Engineering and Technology E-ISSN , P-ISSN INPRESSCO, All Rights Reserved Available at Research Article Study on Tool Parameters of Al2O3 in High Speed Machining Prabhakar Mutukundu * and Yathish Narayana Rao K.V Department of Mechanical Engineering, Vishweshwaraiah Technological University, Belgaum, Karnataka, India Accepted 15 Jan 215, Available online 1 Feb215, Vol.5, No.1 (Feb 215) Abstract In this project work, experimentally modeling of dry high speed machining at cutting speed range of 8 to 6 using Al 2O 3 turning insert. Studied the turning process parameters (cutting speed, feed rate and depth of cut) for mac hining of EN-24T alloy steel with an cutting tool Al 2O 3 & Carbide turning insert at cutting velocity range between 8 t o 6 (45 to rpm) with feed rate of.1 to 5mm/rev and depth of cut of.1 to.5 mm. Experiments we re repeated for -6, and +6 rack angles of Al 2O 3 tool. Performed simulation of turning operation using Finite Eleme ntal Method () techniques at the same cutting speed, Feed rate and depth of cut ranges for the +6 tool and cuttin g forces are measured from analysis. Performance of Al 2O 3 tool was compared with Carbide tool a nd validated with analysis. Calculated percentage of of cutting forces of experimental and results o f Al 2O 3 tool. Keywords: High speed machining, measurement of cutting forces, machining of EN24T steel, Al 2O 3 tool 1. Introduction 1 Among the most effective and efficient modern manufacturing technologies, high speed machining (HSM) is employed to increase productivity while simultaneously improving product quality and reducing manufacturing costs. Depending on work and tool materials as well as tool life requirements, the cutting speed used in HSM is often 2 5 times higher than those employed in traditional (relatively low speed) machining. Due to its high material removal rate and short product cycle time, HSM has received steadily growing applications in recent years in many industrial sectors, such as defense, aerospace, aircraft, automotive, and die- and moldmaking (N. Fang 8).To improve the productivity and reduce the cost of manufacturing, one of the popular choices is to go with high speed machining. High speed machining involves very high strain rates. Advances in ceramic processing technology have resulted in a new generation of high performance ceramic cutting tools exhibiting improved properties. Improvements have been made in tool properties such as fracture strength, toughness, thermal shock resistance, hardness and wear resistance. These developments have now enabled the ceramic tools to be used in the machining of various types of steel, cast iron, non-ferrous metals and refractory nickel based alloys at high speed. Aluminum oxide is widely used as ceramic cutting tool material and it is strengthened by *Corresponding author: Prabhakar Mutukundu the addition of particles like zirconium oxide, titaniumcarbide, and titanium nitride to improve the properties (Senthil Kumar, 3). Ceramic cutting tools have an advantage in the machining of hard work piece materials at high speed. The of main cutting force with cutting speed on machining EN 24 steel (45HRC) using Ti[C,N] mixed alumina ceramic cutting tool is presented in Figure. It can be noted from the figure that the cutting forces of the ceramic cutting tool decreases with cutting speed. Fig. 1 Comparison of main cutting force with cutting sp eed on machining EN 24 steel with 4HRC and 45 HRC using Ti[C,N] mixed alumina ceramic cutting tool. The decrease of cutting force with respect to cutting speed when using Ti[C,N] mixed alumina ceramic 184 International Journal of Current Engineering and Technology, Vol.5, No.1 (Feb 215)

2 Prabhakar Mutukundu et al cutting tool shows that this type of ceramic cutting tool can machine the work piece material with high speed and at low cutting forces. The lower cutting forces, result in a lower distortion of work piece, which improves the surface finish while machining with the ceramic cutting tools and particularly by using Ti[C,N] mixed ceramic cutting tools (Senthil Kumar, 3). [Charles W 1988],These ceramic composite cutting tool materials are being used primarily for machining of hard materials like cast iron, steel, stainless steel in their hardened conditions, refractory metals like nickel-based alloys and composite materials. The need for finish machining operation like grinding can be eliminated by using these ceramic composite cutting tools. It was reported that switching from coated carbide tools to composite ceramic tools had resulted in a 2.5 times improvement in tool life plus faster metal removal rate when machining automobile axle hubs made out of malleable iron [Yang Zhenchao, 1997] was simulated The turning process of Inconel 718 by the commercial general purpose machining software Advant-Edge and the influences of cutting speed, feed and cutting depth on cutting force and temperature are analyzed. In the experimental range, the cutting forces decrease with cutting speed increasing, and increase with feed and cutting depth increasing. The influence of cutting depth on cutting forces is significant. study on tool parameters of Al2O3 in high speed marching Depth of cut I/P power to the.1,.2,.3,.4,.5 mm 7.5kW The cutting experiments involved Carbide tool and Al 2O 3 with rack angle -6, & +6. Six levels of cutting speeds, and five levels of feed rates & depth of cuts. No cutting fluids or coolants were employed in order to facilitate the collection of the cutting force data.as shown in Table 2, the employed cutting speeds ( ) were at least three times higher than those used in traditional machining of the two work materials. Fig. 2 shows the experimental set up on CNC turning center. 2. set-up and methods of cutting force measurements Table 2 summarizes the experimental set-up, where a total of 64 orthogonal high speed turning experiments were performed on a CNC turning center (PMT BC). Table 1Details of Al 2O 3 tool used in the experiments. Details of tool material Alumina Ti[C,N] mixed tool Composition Al2O3 +TiCN Insert Specification TNMGAB3 Density 4.25 g/cm 3 Vickers hardness 193 (HV3) Young's Modulus 4 GPa Fracture toughness 4.5 MPa m Thermal conductivity 2 W/mK Table 2 set-up Category Value Work material EN24T Alloy steel Workpiece diameter 55mm Tool insert TNMG AB3 (Teague Tec) Tool material Ceramic ( Al2O3 +TiC) Rack angles -6, & +6. Tool edge radius.4 mm Tool holder MTJNL2525M22 Cutting speed 86, 173, 259, 345, 432& 518 Feed rate.1,.2,.3,.4,.5 mm/rev Fig. 3 Photographic view of CNC machine FANUC system output screen display 2.1 Measurement of cutting forces As the tool start progress into the tool, reaction forces will act on the tool edge radius. These forces transferred to the spindle and FANUC system convert this forces into percentage of load on the machine (power consumed).the following formulas are used to calculate the cutting forces from the output of CNC FANUC system display. Work done = power (P) needed for turning = (F c x V c/6)+(f D x V c/6)+ (F f x V c/6) (1) Since there is no radial movement of tool in turning, 185 International Journal of Current Engineering and Technology, Vol.5, No.1 (Feb 215)

3 Cutting force (N) Cutting force, N Prabhakar Mutukundu et al there is no work done by the radial component of force. P = (F c x V c/6)+(f f x V c/6) (2) P = (F c x V c/6) (3) Where Force is in Newton and V is in, F c = Tangential forces, F D = Radial forces in F f = Feed forces 3. Finite Element Analysis modeling The simulation of turning operation on EN24Tsteel using Al 2O 3 tool with +6 rack angle has been performed using Finite element method techniques. Abacus 6.12 version CAE software is used. 3D geometry of work piece and tool are created in the abacus and are as shown in the fig. 4. study on tool parameters of Al2O3 in high speed marching 4.1 Comparative study of experimental results Fig. 3 shows the comparison for of cutting forces with respect to cutting velocity for carbide and Ceramic tool. The behavior of cutting forces for both the tools is similar and magnitude of cutting force for ceramic tool is higher because of dry machining. From the figure 6, it is noticed that, for Al 2O 3 tool the cutting forces are reducing significantly during the speed range of 8 to 18 and after that gradually reducing Carbide Al2O3 (-6 ) Al2O3 ( ) Al2O3 (+6 ) Al 2 O 3 (-6 ) Al 2 O 3 ( ) Al 2 O 3 (+6 ) Cutting speed, Fig. 4 Assembly view of work piece and cutting tool. A tetrahedral mesh is used which is an 8-node linear tetrahedron with Abacus designation C3D8R, the DOF of each node is 3. The mesh properties as shown in the table 3. The work piece is fixed in the all linear motion and rotation motions and the tool is allowed only x- direction translation motion. Fig.5 shows the boundary condition of work piece and cutting tool Carbide Al2O3 (+6 ) Al2O3 ( - ) Al2O3 ( -6 ) Fig. 5 Boundary conditions of work piece and cutting tool 4. Results and Discussion In the present investigation, analysis of cutting forces during the turning of EN24 steel using carbide and Ceramic tool insert with -6, & +6 rack angles has been carried out on CNC turning center. Also, simulation of turning operation for EN24 steel by finite element method has been carried out for ceramic tool. The results of Al 2O 3 & Carbide tool from experimental set up have been compared and the Al 2O 3 experimental results have been validated with results Feed rate, m 186 International Journal of Current Engineering and Technology, Vol.5, No.1 (Feb 215) Carbide Al2O3 ( 6 ) Al2O3 ( ) Al2O3 ( -6 ) Depth of cur, mm (c) Fig. 6 Variation of cutting forces with respected to cutting speed, Feed rate & (c) Depth of cut

4 Cutting forces (N) Prabhakar Mutukundu et al The magnitude of cutting forces for carbide tool is less comparatively because of dry machining. As commonly it is notices that the magnitude of the cutting forces are decreasing as the rack angle increases from -6 to +6. This is because of the force exerted by chip on the cutting tool edge/face is less as the rack angle increases from negative to positive. 4.2 Validation of Al 2O 3 Result with results The results obtained by are noted and plotted the graphs as shown in figures. Here the forces extracted by are compared with forces extracted from experimentally for the process parameters of cutting speed 86 to 512 (45 to rpm), feed rate.25 mm/rev and.5 mm respectively. study on tool parameters of Al2O3 in high speed marching to chip out or tool fractures and frictional forces between tool and work piece Cutting Velocity, Feed rate, Fig. 7 Screen image of results for Cutting velocity, 86 to 518, feed rate.25, rev/min & cutting depth,.5mm. Cutting forces after 3sec of tool travel. Cutting forces after 6 sec of tool travel Considering this result, it is observed that the experimental result is similar to the analysis. There is some deviation in the value cutting forces, this deviation may occur due to the some possible measurement errors in experimental test, such as machine operating experience, setting of process Parameters, manufacturing defects in specimen, eccentricity present at the time of machining and due Depth of cut, mm 187 International Journal of Current Engineering and Technology, Vol.5, No.1 (Feb 215) (c) Fig. 8 Comparison of cutting forces from experimental & results with respect to Cutting speed, Feed rate & (c) Depth of cut. 4.3 Percentage Deviation of cutting forces from experimental & results of Ceramic tool As part of validation of experimental results of Al 2O 3 tool, cutting forces values which results from experimental and results are tabulated and calculated percentage of deviation between both the values.

5 Prabhakar Mutukundu et al Table 3 cutting speed Vs Cutting forces for Al 2O 3tool with +6 rack angle Cutting velocity, Cutting forces,n Table 4 Feed rate Vs Cutting forces for Al 2O 3tool with +6 rack angle Feed rate, Table 5Depth of cut Vs Cutting forces for Al 2O 3tool with +6 rack angle Depth of cut, mm Conclusion The high speed turning operation of EN24T steel alloy using Al 2O 3 cutting tool with different rack angles is conducted on CNC turning machine and the influences of cutting speed, feed and cutting depth on cutting force are analyzed. In the experimental range, the following conclusions are based on the results above: 1) An increase in the cutting speed leads to a gradual decrease in the cutting forces. It should be noted that the cutting conditions employed did not favor any material adherence on tool cutting edge. It is observed that the forces (N) decreased quickly in the interval 8 18, and reduced by 34.%, however, these drops are only 2.6% between 18 and 52 2) The results presented on Fig. 6 show the evolution of the cutting forces according to the feed rate. If the feed rate increases, the section of sheared chip increases because the metal resists study on tool parameters of Al2O3 in high speed marching the rupture more and requires larger efforts for chip removal. 3) It is observed that the cutting force increases with cutting depth increasing because of the area of cut per tooth increasing. 4) Based on experiments conducted with three different rack angles, it is noticed that cutting forces on tool is decreases as the rack angle increases from negative to positive 5) From Fig. 8, it is validated that the behavior of experimental results is similar to the analysis. There is some deviation in the value cutting forces, This deviation may occur due to the some possible measurement errors in experimental test, such as machine operating experience, setting of process parameters, manufacturing defects in specimen, eccentricity present at the time of machining and due to chip out or tool fractures and frictional forces b/w tool and piece References N. Fang, Q. Wu,(8) Comparative study of the cutting forces in high speed machining of Ti 6Al 4V and Inconel 718 with a round cutting edge tool,journal of Materials Processing Technology Senthil Kumar, (1988) Machinability of hardened steel using alumina based ceramic cutting tools, pp Charles W, (1988) Ceramic cutting tools update. Manufacture Eng., pp Yang Zhenchao, (1997) The Simulation of Cutting Force and Temperature Field in Turning of Inconel 718,Journal of Materials Processing Technology, pp H.M Somashekar, N.Laksmana Swamy, Chandrasekhar B, Effective Method to measure Cutting Forces during High Speed Machining of Aluminiumil,International journal of advanced science and technologies,vol No. 6, issue No. 2, pp Donaldson,LeCAIN, GOOLD, TOOL DESIGN 3 rd Edition, Page number 226. Milton C. Shaw.,(9) Metal Cutting Principles, CBS publishers and distributors, 1 st Edition, 9, pp Jeremy M. Schreiber, (213) High-strain-rate property determination of high-strength steel using finite element analysis and experimental data. MaanAabidTawfiq, and Suha Kareem Shahab,(7) A Finite Element Analysis of Orthogonal Machining Using Different Tool Edge Geometries.Eng. & Technology, Vol.25, No.4, pp Limido.J.et al.,(7) SPH method applied to high speed cutting model. International journal of mechanical science, Vol.49, pp MahendraKorat, NeerajAgarwal, (212) Optimization of Different Machining Parameters of En24 Alloy Steel In CNC Turning by Use of Taguchi Method, International Journal of Engineering Research and Applications, Vol. 2, Issue 5, pp Manjunatha,R. and Umesh.C.K,(212) Application of Taguchi technique for the optimization of forces and surface finish during the machining of steel en-19 using an uncoated carbide tool insert,journal of Manufacturing Engineering, Vol. 7, pp International Journal of Current Engineering and Technology, Vol.5, No.1 (Feb 215)